Mycotoxins are secondary metabolites secreted by a variety of fungi, often produced in cereal grains as well as forages before, during and after harvest. Forages and cereals naturally come into contact with fungal spores. The fungal contamination of plants and the bio-synthesis of toxins depend on the state of health of the plant before harvest, meteorological conditions, harvesting techniques, delays and hydrothermal conditions before stabilization for conservation and feed processing. Depending on the fungus, fungal growth is controlled by a number of physico-chemical parameters including the amount of free water (aw), temperature, presence of oxygen, nature of the substrate, and pH conditions. Mycotoxins proliferate pre-harvest as well as post-harvest in storage.
Some fungi produce toxins only at specific levels of moisture, temperature or oxygen. The effects of mycotoxins vary greatly in their severity. Some mycotoxins are lethal, some cause identifiable diseases or health problems, some weaken the immune system without producing symptoms specific to that mycotoxin, some act as allergens or irritants, and some have no known effect on animals or humans. During World War II Russian soldiers suffered severe dermal necrosis, hemorrhage and destruction of bone marrow after eating moldy grains that were contaminated with Fusarium. However, it was not until the 1960's, when more than 100,000 turkeys of Britain were decimated by a fatal liver disease (Turkey X Disease) that the scientific community recognized the negative effects associated with mycotoxins (See, e.g., Trenholm H. L., Charmley L. L., and Prelusky D. B., 1996. Mycotoxin binding agents: An update on what we know. In: Biotechnology in the Feed Industry (Lyons T. P and Jacques K. A eds.) Nottingham University Press, Loughborough, Leics, UK, pp. 327-349). According to recent United Nation's Food and Agriculture Organization (FAO) reports, approximately 25% of the world's grain supply is contaminated with mycotoxins. Mycotoxin contamination has a negative economic impact on food and feed producers, particularly grain and poultry producers.
Mycotoxins can appear in the food chain as a result of fungal infection of plant products (e.g., forage, grain, plant protein, processed grain by-products, roughage and molasses products), and can either be eaten directly by humans, or introduced by contaminated grains, livestock or other animal feedstuff(s). Mycotoxins greatly resist decomposition during digestion so they remain in the food chain in edible products (e.g., meat, fish, eggs and dairy products) or under the form of metabolites of the parent toxin ingested. Temperature treatments such as cooking and freezing are not adequate methods of decreasing the prevalence of mycotoxins. Thus, there exists a need for compositions and/or methods for reducing the detrimental effects and/or eliminating mycotoxin occurrence in feed and/or food chains.